Using the morphology and magnetic fields of tailed radio galaxies as environmental probes

TL;DR

Bent-tailed radio galaxies serve as powerful probes of large-scale structures, environmental conditions, and magnetic fields in the universe, especially at high redshifts, offering insights into cluster dynamics and magnetic coherence lengths.

Contribution

This paper introduces a novel approach to using bent-tailed radio galaxies, particularly corkscrew types, as environmental probes for large-scale structure, intra-cluster medium, and magnetic fields.

Findings

BTs trace over densities up to z ~ 2

BT morphology reveals local environmental conditions

Corkscrew BTs can elucidate magnetic field coherence lengths

Abstract

Bent-tailed (BT) radio sources have long been known to trace over densities in the Universe up to z ~ 1 and there is increasing evidence this association persists out to redshifts of 2. The morphology of the jets in BT galaxies is primarily a function of the environment that they have resided in and so BTs provide invaluable clues as to their local conditions. Thus, not only can samples of BT galaxies be used as signposts of large-scale structure, but are also valuable for obtaining a statistical measurement of properties of the intra-cluster medium including the presence of cluster accretion shocks & winds, and as historical anemometers, preserving the dynamical history of their surroundings in their jets. We discuss the use of BTs to unveil large-scale structure and provide an example in which a BT was used to unlock the dynamical history of its host cluster. In addition to their use as density and dynamical indicators, BTs are useful probes of the magnetic field on their environment on scales which are inaccessible to other methods. Here we discuss a novel way in which a particular sub-class of BTs, the so-called `corkscrew' galaxies might further elucidate the coherence lengths of the magnetic fields in their vicinity. Given that BTs are estimated to make up a large population in next generation surveys we posit that the use of jets in this way could provide a unique source of environmental information for clusters and groups up to z = 2.